Forza 5 becomes the second Microsoft-published Xbox One title to reach the 1 million mark, following Dead Rising 3, though that game has shipped, not sold, 1 million copies. One million sales for Forza 5 means the game is now the "best-selling racing game by console attach over the past decade," based on worldwide sales data as of February 2014.

This is one of the first instances we can recall of sales being measured by attach rate. In short, Microsoft claims that the percentage of people who own Forza 5 is higher than for any other racing game based on the number of consoles sold. The data point is somewhat odd because the Xbox One install base will continue to grow, which means the attach rate will conceivably fall.

Microsoft also released a handful of Forza 5 statistics regarding player engagement levels with the racing game. These are listed below.

Players have driven over 653 million miles (equivalent of circling the planet 49,223 times).

Players have participated in over 94 million races for a total of 8 million hours of gameplay.

Drivatars have populated friends' races and challenges to the tune of over 1 billion races.

To mark the sales milestone, Microsoft today launched "Road America," the first track add-on for Forza 5. It is available to download today for free and will be automatically added into the Career events menu. Lastly, the Road America booster pack is also available today. It features five cars and is free for Car Pass owners through May 2014. The included cars are listed below.